A variety of surgical instruments are employed in various open, endoscopic, and laparoscopic surgeries. One group of such instruments is utilized to manipulate tissue, seal tissue, and/or transect tissue. These instruments can include a distal end effector having opposed jaw members that move relative to one another to grasp tissue therebetween. Certain of these instruments can also include a cutting mechanism that can be advanced through the grasped tissue to transect it. Electrical or other energy can also be delivered to the grasped tissue to seal the tissue prior to, or concurrent with, transection. For example, electrical energy can be applied to the grasped tissue by various mono-polar and bi-polar radio frequency (RF) electrodes or other energy delivery structures coupled to the jaw members. In other embodiments, ultrasonic energy can be applied to tissue by an oscillating element to effect tissue sealing and transection.
These surgical instruments often include a proximal actuating portion from which the distal end effector can be controlled. The proximal actuating portion can include a plurality of triggers or other control mechanisms to control the various functions of the instrument. For example, a first trigger can control the opening or closing of the jaw members to grasp tissue, while a second trigger can control the operation of a cutting mechanism and/or the delivery of energy to seal tissue. In use, a user can actuate the first trigger and hold or latch it in an actuated or closed position to securely grasp and compress tissue between the first and second jaw members, then the user can actuate the second trigger to transect and/or seal the tissue.
Certain surgical instruments can also include an articulating portion that allows the end effector to be moved relative to the actuating portion. For example, an articulating portion can be included in some instruments along the length of a shaft that connects the distal end effector to the proximal actuating portion. The articulating portion can permit the end effector to be positioned such that a longitudinal axis of the end effector is transverse, or non-parallel, to a longitudinal axis of the actuating portion or the shaft extending therefrom. The ability to articulate the end effector relative to the actuating portion can be valuable, as it can permit the instrument to access tissue and perform surgical operations that might not otherwise be possible, or at least might be more difficult or physically awkward to perform with a straight shaft instrument.
A number of different configurations for articulating portions are known in the art, but often include associated disadvantages. For example, some known designs employ a series of segmented sections wherein each section has a certain degree of freedom to move relative to an adjacent section. Utilizing one or more of these sections can allow for varying degrees of articulation. Unfortunately, known segmented articulating portions often lack desired levels of stiffness when subjected to compressive axial loads. For example, if a user attempts to push such an instrument through tissue or a tight opening, prod tissue, dissect tissue, etc., resistance can cause undesirable articulation of the end effector. Moreover, known segmented designs often articulate in unpredictable manners because each adjacent segment is able to articulate in a plurality of directions, e.g., via a plurality of ball-and-socket type interfaces.
Furthermore, some known articulating portion designs include one or more openings or other features formed on an outer surface of the articulating portion. These openings or other features can include, for example, relief slots or other features that can aid articulation. Such features can also have undesired effects, however, including capturing tissue and other debris that can complicate procedures, or allow fluid ingress into the instrument.
Still further, known articulating portion designs can be complex multi-component assemblies. Such designs can have increased manufacturing costs associated therewith and, in the event of device disassembly for sterilization or reuse, can be more costly to process.
Accordingly, there is a need for surgical instruments with improved articulating joints or portions. More particularly, there is a need for such instruments having less complex articulating portions that can match or exceed the performance capabilities of known devices.